(Revised Abstract) DESCRIPTION (provided by applicant): The ability to introduce foreign genes into the mammalian germ line, or to selectively ablate endogenous genes from the mouse genome, has proven to be one of the most powerful experimental tools to understand specific genetic requirements for both developmental and tumor promoting regulatory pathways. These techniques have been enormously useful in elucidating mechanisms of gene regulation and protein function. In the area of oncology, transgenic mice have revealed that overexpression of protooncogenes predispose cells to develop malignant tumors while tumor suppressor genes maintain normal growth control. Transgenic strategies also have revolutionized the way we approach the complex problems associated with carcinogenesis, including issues related to gene regulation, cell-cell interactions, cell cycle control and a variety of signal transduction pathways. The Purdue Cancer Center Transgenic Mouse Core Facility (TMCF) Shared Resource was established in January 1998 through support from NCI and Purdue University to serve the Purdue Cancer Center research community. The TMCF is a state-of-the-art facility that offers the following services; (1) pronuclear injections for the production of transgenic mice, (2) generation of targeted ES cell lines, (3) blastocyst injections or morula aggregation to generate chimeric mice for producing homozygous null animal models, (4) strain rederivation, (5) in vitro fertilization, and (6) embryo cryopreservation. The facility also will offer sperm freezing and MEF isolation services starting in the fall of 2002. The Purdue Cancer Center has been an integral component of our cancer research community, fostering close interactions among active scientists in understanding aspects of experimental therapeutics, structural biology, carcinogenesis and gene regulation. The role of the TMCF is to assist the individual investigators and Program Areas within the Cancer Center that are seeking novel approaches in addressing a variety of cancer related issues. In offering these key transgenic services, the TMCF provides the needed expertise to our investigators to achieve the next challenge in their research goals. Goals that are aimed at addressing a variety of cancer biology issues.